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Form the Differential Equation Representing the Family of Curves Y = a Sin (X + B), Where A, B Are Arbitrary Constant.

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Question

Form the differential equation representing the family of curves y = a sin (x + b), where ab are arbitrary constant.

Sum
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Solution

We have,
y = a sin (x + b)          .....(1)
Differentiating both sides, we get

\[\frac{dy}{dx} = a \cos\left( x + b \right)\]
\[ \Rightarrow \frac{d^2 y}{d x^2} = - a \sin\left( x + b \right) \]
\[ \Rightarrow \frac{d^2 y}{d x^2} = - a \times \frac{y}{a} ...............\left[\text{Using (1)} \right]\]
\[ \Rightarrow \frac{d^2 y}{d x^2} = - y \]
\[ \Rightarrow \frac{d^2 y}{d x^2} + y = 0\]

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Chapter 21: Differential Equations - Revision Exercise [Page 145]

APPEARS IN

R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 21 Differential Equations
Revision Exercise | Q 5 | Page 145

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